The Long Dark Tea-Time of the Soul (Dirk Gently, #2), The Hitchhiker's Guide to the Galaxy: A Trilogy in Four Parts, The Restaurant at the End of the Universe (Hitchhiker's Guide, #2), Mostly Harmless (Hitchhiker's Guide, #5), Young Zaphod Plays It Safe (Hitchhiker's Guide to the Galaxy, #0.5), So Long, and Thanks for All the Fish (Hitchhiker's Guide, #4), Dirk Gently's Holistic Detective Agency (Dirk Gently #1), Life, the Universe and Everything (Hitchhiker's Guide, #3), The Hitchhiker's Guide to the Galaxy (Hitchhiker's Guide, #1), The Ultimate Hitchhiker's Guide to the Galaxy